multiprocessing python code

Question

When I try to paralellize python code I get an assertion error. Here is the code :

check = Parallel(n_jobs=ncpu)(delayed(removeident)(h) for h in splitframe)

individually, each element (h) in splitframe works well with the function removeident that is removeident(h) yields expected results.

The error message is on the console :

AssertionError: _ _main_ _
Traceback (most recent call last):
   File "<string>"; line 1, in <module>
   File"C:\Python27\lib\multiprocessing\forking.py"; line 380, in main prepare  (preparation_data)
   File"C:\Python27\lib\multiprocessing\forking.py"; line 488, in prepare assert main_name not in sys.modules, main_name 

What could the problem be?